Cledonismancy of cledonomancy is divination by the first words heard upon meeting friends, waking up, or leaving home. it is derived from the ancient Greek 'kledonisma,' meaning a sign or omen.
According to Cicero, the Pythagoreans were very attentive to such omens. The Encyclopedia of Religion and Ethics says ancient practicioners of this form of divination would whisper questions into the god's ear. Then blocking up his or her own ears, went out and after moving a certain distance, would listened for chance words from passersby. These were taken as an answer.